Method for manufacturing an endoscope insertion tube, and endoscope having an insertion tube

ABSTRACT

The invention relates to a method for manufacturing an endoscope insertion tube ( 2 ).The insertion tube ( 2 ) has a proximal passive flexible section ( 20 ) and a distal angled section (A). The entire insertion tube, including the passive flexible section ( 20 ) and the angled section (A), is formed from a single tube element. The invention further relates to an endoscope having such an insertion tube ( 2 ).

The present invention relates to a method for manufacturing an endoscopeinsertion tube, and an endoscope having an insertion tube.

An endoscope is a device that may be used to examine the interior ofliving organisms, and also technical cavities. The flexible insertiontube is an important part of an endoscope. The demands on an insertiontube are considerable and numerous. On the one hand, it must be flexibleto allow it to be introduced into the human body. On the other hand, theinsertion tube must have a certain rigidity. During the examination, themedical practitioner must be able to push and turn the insertion tube byuse of the control body. The insertion tube must be rigid enough that itdoes not become kinked or twisted. Therefore, conventional insertiontubes require a very complex construction and high manufacturing costsin order to meet the stated requirements.

To simplify the manufacture of a tube element for medical purposes andto lower the manufacturing costs, in the prior art the concept hasarisen of manufacturing a tube element for medical purposes from asingle hard tube. Various highly precise cuts are made on the hard tubewith a laser cutting machine. Due to the cuts, a hard tube is flexiblebut can maintain rigidity. The flexibility and rigidity of the tube maybe controlled via the shape, arrangement, and size of the cuts.

The object of the present invention is to provide a method formanufacturing an endoscope insertion tube and for providing an endoscopehaving an insertion tube, which are less complex and by means of whichthe costs may be even further reduced.

With regard to the method, the object is achieved by a method having thefeatures of claim 1. An endoscope having an insertion tube is set forthin claim 13. Advantageous refinements are the subject matter of thedependent claims.

In the invention, in the method for manufacturing an endoscope insertiontube, the entire insertion tube, including the proximal passive flexiblesection and the distal angled section, is formed from a single tubeelement.

Thus, it is necessary to provide only one tube element. A joiningoperation between the proximal passive flexible section and the distalangled section is dispensed with. The production costs are lower than inprevious methods for manufacturing an insertion tube.

In this method, the entire insertion tube, including the angled section,may be cut from a single tube element via laser. The machining by laserallows a very precise design of the overall insertion tube.

In this method, individual cuts may be made in the tube element, and themanufacture is simple and cost-effective.

In this method, the distal angled section has inwardly bent guideprotrusions on which a traction cable is supported; the inwardly bentguide protrusions are cut from the circumferential wall of the distalangled section and then bent inwardly. In this way, guides for atraction cable are easily produced on the inner circumferential side ofthe angled section.

In this method, at the transition from the proximal passive flexiblesection and the distal angled section, the insertion tube has aninwardly bent bracket on which a guide spring is supported; the inwardlybent bracket is cut from the circumferential wall of the insertion tubeand then bent inwardly. The number of inwardly bent brackets on which aguide spring is supported corresponds to the number of guide springs,and thus, to the number of traction cables. In this way, guides forguide springs are easily produced on the inner circumferential side ofthe insertion tube.

In this method, multiple articulated joints may be produced in thecircumferential wall of the distal angled section by cutting. Individualarticulated joints that form independent bodies and are joined togetherin a form-fit manner are easily and cost-effectively produced.

In this method, the particular articulated joint produced by cutting hasa coupling section that is coupled to an adjacent articulated joint,produced by cutting, in such a way that an axial movement, but not aradial movement, of the articulated joints relative to one another isblocked, and a guide section that engages with an adjacent articulatedjoint, produced by cutting, in such a way that an axial movement of thearticulated joints relative to one another is made possible. Adjacentarticulated joints are coupled to one another via the coupling section,and adjacent articulated joints are axially movable relative to oneanother via the guide section.

In this method, the proximal passive flexible section is produced byrespective lateral indentations that are provided perpendicular to thelongitudinal extension of the tube element. The proximal passiveflexible section may be quickly and easily manufactured in this way.

In this method, in the longitudinal extension of the tube element theproximal passive flexible section has at least two subsections whichinclude the respective lateral indentations at different spacings fromone another in the longitudinal extension of the tube element. Multipleseparate subsections having different degrees of flexibility andbendability with respect to one another may thus be formed in theproximal passive flexible section.

In this method, the tube element may be made of stainless steel. Thecuts may be easily made, and the material costs are low.

In this method, the tube element may be made of plastic. Any suitableplastic having sufficient strength may be used. The plastic only needsto be able to provide the bendability of the finished insertion tube.

In this method, from a control body situated proximally from theproximal passive flexible section, a traction cable may be situated onthe inner circumferential side of the tube element, wherein at anarticulated joint of the distal angled section situated farthestdistally, the traction cable is led through a first slot in a wall ofthe tube element to the outer circumference of the tube element, aroundthe outer circumference of the tube element, to a second slot in thewall of the tube element to the inner circumference of the tube element,wherein the second slot is opposite the first slot by 180 degrees, andis led back to the control body on the inner circumferential side of thetube element. Particularly cost-effective anchoring of the tractioncable to the distal side of the angled section may be achieved in thisway.

An endoscope according to the invention has an insertion tube, theinsertion tube having a proximal passive flexible section and a distalangled section. The entire insertion tube, including the passiveflexible section and the angled section, is formed from a single tubeelement.

The distal angled section may have inwardly bent guide protrusions onwhich a traction cable is supported.

At the transition from the proximal passive flexible section and thedistal angled section, the insertion tube may have an inwardly bentbracket on which a guide spring is supported.

Multiple articulated joints may be formed in the circumferential wall ofthe distal angled section.

The particular articulated joint may have a coupling section that iscoupled to an adjacent articulated joint in such a way that an axialmovement, but not a radial movement, of the articulated joints relativeto one another is blocked, and a guide section that engages with anadjacent articulated joint in such a way that an axial movement of thearticulated joints relative to one another is made possible.

The tube element may be made of stainless steel or plastic.

From a control body situated proximally from the proximal passiveflexible section, a traction cable may be situated on the innercircumferential side of the tube element, wherein at an articulatedjoint of the distal angled section situated farthest distally, thetraction cable is led through a first slot in a wall of the tube elementto the outer circumference of the tube element, around the outercircumference of the tube element, to a second slot in the wall of thetube element to the inner circumference of the tube element, wherein thesecond slot is opposite the first slot by 180 degrees, and is led backto the control body on the inner circumferential side of the tubeelement.

The aspects of the present invention described above may beappropriately combined.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a schematic side view of an endoscope for which theinvention may be applied.

FIG. 2 shows a cut-away schematic view of an insertion tube according tothe invention.

FIG. 3 shows a cut-away schematic view of a portion of a proximalpassive flexible section of the insertion tube according to theinvention.

FIG. 4 shows a cut-away schematic view of a transition area between thedistal angled section and the proximal passive flexible section of theinsertion tube according to the invention, a guide spring fixing sectionbeing shown.

FIG. 5 shows a cut-away perspective view of the guide spring fixingsection from FIG. 4, from another side.

FIG. 6 shows a cut-away schematic view of a portion of the angledsection of the insertion tube according to the invention.

FIG. 7 shows a cut-away schematic view of the portion of the angledsection of the insertion tube according to the invention, a view fromthe direction of an arrow I from FIG. 6 being shown.

FIG. 8 shows a cut-away schematic view of a portion of the angledsection of the insertion tube according to the invention, a cable guidebeing shown.

FIG. 9 shows a cut-away perspective view of the cable guide from FIG. 7.

FIG. 10 shows a cut-away schematic side view of the angled section ofthe insertion tube according to the invention.

FIG. 11 shows a cut-away schematic top view of the angled section fromFIG. 10.

FIGS. 12 through 14 each show a cut-away perspective view of the distalend of the angled section.

FIG. 15 shows a cut-away perspective view of the traction cable anchoron the distal end of the angled section.

FIG. 16 shows a view, corresponding to FIG. 15, from another side.

FIG. 17 shows a bending section of a second exemplary embodiment in aside view.

FIG. 18 shows a top view of a distal area of the bending section of thesecond exemplary embodiment.

FIG. 19 shows a cross-sectional view of the bending section of thesecond exemplary embodiment.

The present invention is described in greater detail below based onexemplary embodiments, with reference to the drawings.

First Exemplary Embodiment

A first exemplary embodiment of the present invention is described belowwith reference to FIGS. 1 through 16.

Firstly, FIG. 1 shows a schematic side view of an endoscope 1 for whichthe invention may be applied. It is apparent from FIG. 1 that such anendoscope 1 has an insertion tube 2 situated on the distal side of acontrol body 3. The control body 3 is used as a control unit for theendoscope 1.

The insertion tube 2 is a cylindrical tube- or hose-like structure.

The insertion tube 2 is described in greater detail below with referenceto the direction in which it is inserted into a patient. The insertiontube 2 is inserted with the distal end leading.

The insertion tube 2 has a distal angled section A on the distal side.The angled section A may be laterally bent relative to the proximalportion of the insertion tube 2 by means of one or more control wires(cable pulls). The control wire or cable pull (referred to below only as“control wire”) is supported in a guided manner inside the insertiontube 2 on an inner circumferential surface of the insertion tube 2 inthe direction of extension of the insertion tube 2.

The distal end of the control wire is anchored on the distal side of theangled section A. The proximal end of the control wire is connected to acontrol element situated in the control body 3. This control elementtensions the control wires in order to achieve desired bending of theangled section A.

Proximal from the angled section A, the insertion tube 2 is designed asa flexible tube element that forms a proximal passive flexible section20. When the insertion tube 2 is inserted, the flexible section 20follows the angled section A.

It is shown in FIG. 1 that the flexible section 20 along itslongitudinal direction is formed in zones having different degrees offlexibility. For example, the flexible section 20 has a first zone B, asecond zone C, and a third zone D, viewed in the proximal direction. Thefirst zone B forms a distal area, the second zone C forms a middle area,and the third zone D forms a proximal area.

The third zone D is not shown in the cut-away illustration in FIG. 2.

To avoid buckling between the angled section A and the first zone B, thefirst zone B is preferably provided with the highest flexibility of thezones in the flexible section 20. Since the first zone B is providedwith very high flexibility, there is no abrupt transition of theflexibility between the angled section A and the first zone B.

The second zone C has less flexibility than the first zone B. The thirdzone D in turn has less flexibility than the second zone C.

The insertion tube 2 according to the invention is formed from a singlepiece. That is, two elements are not joined together at the transitionfrom the angled section A to the flexible section 20. Thus, the distalangled section A and the proximal passive flexible section 20 are formedfrom a single tube or hose having the three zones A, B, and C.

On the proximal side, the insertion tube 2 is fixed to the distal end ofthe control body 3. The insertion tube 2 may be fixed to the controlbody 3, for example by means of a locking ring or a sealing ring, ordirectly. The insertion tube 2 may be adhesively bonded or screwed, forexample, to the control body 3. The control body 3 has a first controlwheel F, as a first control element, for controlling a control wire orcable pull, and a second control wheel G, as a second control element,for controlling a control wire or cable pull. The first control wheel Fmay bend the angled section A in a first plane (for example, toward andaway from the observer in FIG. 1) by pulling a control wire or cablepull. The second control wheel G may bend the angled section A in asecond plane that is perpendicular to the first plane (for example, upand down in FIG. 1) by pulling a control wire or cable pull.

The angled section A may be bent by 200-270 degrees, for example. Thisis sufficient for most applications. In one special form, the angledsection A may even be bent by 300 degrees.

The insertion tube 2 according to the invention and its manufacture aredescribed in greater detail below.

The overall insertion tube 2 is formed from a single tube element orhose element (referred to below simply as “tube element”). The tubeelement is a tube made of a preferably relatively hard material,particularly preferably stainless steel. However, a tube made of hardplastic may also be used. In principle, however, any material that isusable for medical purposes may be employed.

Cuts are provided in the tube element by a laser cutting machine, asexplained in greater detail below. After the cuts are provided, certainsubsections of the tube element are bent, as explained in greater detailbelow. In the manufacture of the base body of the overall insertion tube2, no further method steps are necessary besides providing cuts andbending. The base body of the insertion tube 2 may be subsequentlyprovided with a control wire and encased with a sheath element.

The individual sections of the insertion tube 2 are described in greaterdetail below.

Flexible Section 20

The flexible section 20 forms the proximal portion of the insertion tube2 according to the invention. The flexible section 20 has the threezones B, C, and D, each having different degrees of flexibility.

FIG. 3 shows one option for forming one of the three zones B, C, and Dof the flexible section 20, in a side view.

The flexible section 20 is provided with a plurality of cuts S orientedperpendicularly with respect to the axis of the flexible section 20.More precisely, the cuts S are configured in such a way that a cut 201is made from above, through the tube element perpendicular to the axisof the tube element, to a depth that ends prior to the center axis area.In addition, a cut 202 is made from below, through the tube elementperpendicular to the axis of the tube element, to a depth that likewiseends prior to the center axis area. The cuts 201 and 202 are situated ona plane, and their ends are situated opposite from one another with aspace 203 left in between. The space 203 is an uncut space in the centeraxis area of the tube element.

In addition, similarly as for the cuts 201 and 202, a cut 204 is madefrom one (for example, left) side (the cut 204 shows a cut from the sideof the observer), through the tube element perpendicular to the axis ofthe tube element, to a depth that ends prior to the center axis area.Furthermore, a cut is made from the opposite (for example, right) side(this cut is not shown in FIG. 3, since it is situated on the other sideof the plane of the drawing), through the tube element perpendicular tothe axis of the tube element, to a depth that likewise ends prior to thecenter axis area. These cuts are also situated on a plane, and theirends are situated opposite from one another, likewise with a space leftin between. This space is likewise an uncut space in the center axisarea of the tube element.

The space 203 between the cuts 201 and 202 and the space between the cut204 and its associated cut on the opposite side are offset by 90 degreesalong the circumferential direction of the tube element.

The cuts 201 and 202 and the cut 204 and its associated cut on theopposite side are adjacently situated, and alternate with one another inthe flexible section 20 over the length of the particular zone (see FIG.3). D

The flexible section 20 is thus laterally bendable, with respect to itslongitudinal axis, about the spaces.

The individual zones B, C, and D differ in that the spacings between thecuts S in the longitudinal direction, and thus the densities of the cutsS, are different.

The spacing between the cuts S is smallest in zone B. Thus, the densityof the cuts S is highest in zone B.

In zone C the spacing between the cuts S is greater than in zone B. Inzone D, the spacing between the cuts S is greater than in zone C.

Thus, the flexibility and bendability in zone B are greater than in zoneC. In addition, the flexibility and bendability in zone C are greaterthan in zone D. In other words, the flexibility and the bendability ofthe respective zones on the flexible section 20 decrease in the proximaldirection.

On the proximal side, zone D is provided with an area in which no cutsare made. This area forms a transition to the control body J.

Transition from the angled section A to the flexible section 20

The transition area from the angled section A to the flexible section 20is denoted as area K in FIG. 2. The angled section A ends in this areaK. In other words, the first member of the angled section A, i.e., themember proximally farthest, is distal from the area K.

As shown in FIG. 2, in this area K the wall surface of the tube elementis incised by a cut 70 in the shape of a backward letter C. In otherwords, the cut 70 is made in the tube element in the shape of anincomplete circle. The circle of the cut 70 does not go all the waythrough on the distal side. The distal side of the cut 70, which doesnot go all the way through, forms a hinge 71 for a bracket 72. Thebracket 72 has a lower lug 73, an upper lug 74, and a bracket middlepiece 75. The lower lug 73 adjoins on an upper side of the bracketmiddle piece 75. The upper lug 74 adjoins on a lower side of the bracketmiddle piece 75.

The bracket 72 is produced as follows. The location of the cut 70 isspecified. A hole 77 is cut in the center of the cut 70. The cut 70 isformed by laser as shown in FIG. 2. The bracket middle piece 75 issupported from the rear side, i.e., by the inner side of the tubeelement, by a punch. The lower lug 73 is bent inwardly by 90 degreesrelative to the bracket middle piece 75. The bend line of the lug 73relative to the bracket middle piece 75 extends in parallel to the axisof the tube element (in FIGS. 2 and 4, in the directions pointing to theleft and to the right). The upper lug 74 is likewise bent inwardly by 90degrees relative to the bracket middle piece 75. The bend line of thelug 74 relative to the bracket middle piece 75 likewise extends inparallel to the axis of the tube element. The bracket middle piece 75 issubsequently bent inwardly by 90 degrees. The bend line of the bracketmiddle piece 75 relative to the tube element extends in the plane of thecut perpendicular to the axis of the tube element (in FIGS. 2 and 4, inthe directions pointing up and down). In other words, the bracket middlepiece 75 is bent inwardly by 90 degrees at the hinge 71. The bracketmiddle piece 75 is in particular bent inwardly until a distal side edgeof the lower lug 73 and a distal side edge of the upper lug 74 restagainst the inner circumference of the tube element (see FIG. 5).

The bracket 72 is used to support a guide spring 8. In particular, theproximal face of the bracket middle piece 75 forms a stop surface forthe distal end of the guide spring 8. The two lugs 73, 74 support thebracket middle piece 75, and absorb acting pressure forces from theguide spring 8 and further conduct them to the inner circumferentialsurface of the tube element.

The bracket middle piece 75 has the central hole 77. The hole 77 has alarger diameter than a control wire, and a smaller diameter than theguide spring 8. The control wire is guided in the guide spring 8 in theflexible section 20, passes through the hole 70, and extends furtherinto the angled section A.

In area K, brackets 72 are provided in the numerous (in the presentexemplary embodiment, four) control wires used. The brackets 72 areuniformly distributed in the circumferential direction of the tubeelement.

Angled Section A

A more detailed design of the angled section A is shown in FIGS. 6through 11.

The angled section A has individual articulating members 6 situated inthe longitudinal direction of the angled section A. The individualarticulating members 6 are pivotable relative to one another. FIGS. 6and 7 show three articulating members 6 situated in succession: anarticulated joint 61, an articulated joint 62 proximal from thearticulated joint 61, and an articulated joint 63 proximal from thearticulated joint 62.

The articulating members 6 have an identical design, except for thearticulating member 6 situated distally farthest and the articulatingmember 6 situated proximally farthest.

The design of the particular articulating member 6 is explained belowwith reference to the articulating member 62.

The articulating member 62 is formed as a tube section of the statedtube element by laser cutting. The articulating member 62 has distalboundary lines 601, 602, 603, 604, and 605 and proximal boundary lines606, 607, 608, and 609 on the circumference of the tube element.

The individual distal boundary lines are made up of a circularly shapedhead line 601, two neck lines 602, two shoulder lines 603, two arm lines604, and an arm end line 605. More precisely, the distal side of thearticulating member 62 is formed as follows. The circularly shaped headline 601 forms an incomplete circle which at each side merges into aneck line 602 on the proximal side. Each of the two neck lines 602 isadjoined by a shoulder line 603 that extends approximatelyperpendicularly with respect to the axis of the tube element. Each ofthe two shoulder lines 603 is adjoined by an arm line 604 that extendsin the distal direction, approximately parallel to the axis of the tubeelement. The two distal ends of the arm lines 604 are connected by anarm end line 605, which similarly extends perpendicularly with respectto the axis of the tube element.

The articulating member 62 thus has a main body 621, from which a firsthead 622, a first arm 623, a second head 622, and a second arm 623 ineach case protrude by 90 degrees toward the distal side along animaginary circumferential line that extends perpendicularly with respectto the axis of the articulating member 62. The heads 622, 622 thusextend in a first imaginary plane. The arms 623, 623 extend in a secondimaginary plane that is offset by 90 degrees with respect to the firstimaginary plane. The two heads 622, 622 of the articulating member 62form a swivel axis for the distally situated articulating member 61.

Each head 622 is formed by a head line 601 on the distal side. Aconstriction is formed by the neck lines 602, between the head 622 andthe main body 621. Each head 622 protrudes farther in the distaldirection than does the respective arm 623.

The individual proximal boundary lines are made up of a bent foot line606, two base lines 607, two straight foot lines 608, and a stomach line609. More precisely, the proximal side of the articulating member 62 isformed as follows. The bent foot line 606 forms an incomplete circlethat is open on the proximal side. At the open ends of the incompletecircle, the bent foot line 606 in each case merges into the base line607, which in each case extends approximately perpendicularly withrespect to the axis of the tube element.

Each of the two base lines 607 is adjoined by a straight foot line 608that extends approximately parallel to the axis of the tube element inthe distal direction. The two distal ends of the straight foot lines 608are connected by a stomach line 609 which similarly extendsperpendicularly with respect to the axis of the tube element.

On the proximal side of the main body 621, the articulating member 62thus has two feet 624 that extend in the proximal direction. In thedirection of extension, each foot 624 has a straight side on thestraight foot line 608 and a curved side on the bent foot line 606.

An arm of the proximally situated articulating member 63 is situated soas to be displaceable in the longitudinal direction, in the area betweenthe two straight foot lines 608. A head of the proximally situatedarticulating member 63 is held so as to be immovable in the longitudinaldirection in the area between the two bent foot lines 606. In any event,a slight movement due to play between the inner circumference of thebent foot line and the outer circumference of the circularly shaped headline is possible.

In the unbent state of the angled section A, the stomach line 609 isspaced apart from the arm end line 605 of the proximally situatedarticulating member 63, as shown in FIG. 7. The arm end line 605 and thestomach line 609 of the proximally situated articulating member 63 areparallel to one another.

In the unbent state of the angled section A, the base line 607 is spacedapart from the shoulder line 603 of the proximally situated articulatingmember 63, as shown in FIG. 7. The base line 607 and the shoulder line603 of the proximally situated articulating member 63 may be parallel toone another or approximately parallel to one another or slightly angledwith respect to one another, as shown in FIG. 7. Between the base line607 and the shoulder line 603 of the proximally situated articulatingmember 63, not only has a single section line been created, but also thematerial of the tube element has been cut out as a quadrangular piece.

Each head 622 forms a coupling section that is coupled to an adjacentarticulating member 6. The feet 624 form a guide section that engageswith an adjacent articulating member 6 in such a way that an axialmovement of the articulating members 6 relative to one another is madepossible.

FIG. 10 shows a top view of the angled section A with the respectivearticulating members 6. The heads 622 of the articulating members 6 arevisible in the top view.

FIG. 11 shows a side view of the angled section A with the respectivearticulating members 6. The feet 624 of the articulating members 6 arevisible in the side view.

The articulating member 6 situated distally farthest has no head, and isshown in FIGS. 2 and 10 through 14.

The articulating member 6 situated proximally farthest has no foot, andis shown in FIGS. 2, 4, and 11.

In the exemplary embodiment, the angled section A may be bent in twoangular directions, namely, upwardly and downwardly in FIGS. 6 and 7(and FIG. 10), wherein the respective heads 622 of the articulatingmembers 6 form bending axes of the articulating members 6. In otherwords, the angled section A in FIG. 10 is pivotable upwardly anddownwardly. In the illustration in FIG. 11, the angled section A ispivotable toward and away from the observer.

As shown in FIGS. 8 and 9, the stomach line 609 forms a hinge sectionfor a cable guide lug 630. The cable guide lug 630 extends from thestomach line 609. A material section that extends along the straightfoot line 608 to the arm end line 605 of the proximally situatedarticulating member 63 is taken for the cable guide lug 630. The cableguide lug 630 is hinged and bent inwardly by 90 degrees at the stomachline 609. The cable guide lug 630 has a central hole 631. The diameterof the hole 631 is larger than that of the control wire.

Each of the articulating members 6 includes the cable guide lugs 630with the hole 631, so that for a specific control wire, the cable guidelugs 630 are situated in succession in the longitudinal direction of theangled section A. The cable guide lugs 630 are used as guide protrusionson which a control wire is supported. The cable guide lugs 630 thusguide their assigned control wire through the angled section A.

The articulating members 6 may be situated on the angled section A insuch a way that their heads point in the proximal direction, as shown inFIG. 10. Alternatively, the articulating members 6 may be situated onthe angled section A in such a way that their heads point in the distaldirection, as indicated in FIG. 6.

The distal end of the angled section A is shown in FIGS. 12 through 14.The articulating member 69 of the angled section A situated farthest onthe distal side is apparent in FIGS. 12 through 14. The distal side ofthe control wire 9 is anchored in this articulating member 69 situatedfarthest on the distal side. The control wire 9 extends from the controlbody 3 to the articulating member 69 of the angled section A situatedfarthest on the distal side.

Fastening of the Control Wire

The fastening of the control wire 9 is shown in detail in FIGS. 15 and16.

The control wire 9 is fastened to the control wheel G in the controlbody 3. When the control wheel G is rotated in a tensioning direction,the control wire 9 is tensioned. When the control wheel G is rotated inthe tensioning relief direction opposite from the tensioning direction,the control wire 9 is relieved of tension.

The control wire 9 runs from the control body 3, extending in theinsertion tube 2, to the articulating member 69, forming a first section91. This first section 91 of the control wire 9 extends along the innercircumference of the insertion tube 2. This first section 91 of thecontrol wire 9 is denoted by reference numeral 91 in FIG. 15. A slot 691that passes through the circumferential wall of the articulating member69 and extends in the longitudinal direction of the articulating member69 is formed on the distal side of the articulating member 69 (see FIG.13). Another similar slot 692 is provided on the distal side of thearticulating member 69, diametrically opposite from the slot 691.

The control wire 9 extends on the inner circumference of thearticulating member 69 in the distal direction, and passes outwardlythrough the slot 691, is wound on the outer circumference of thearticulating member 69 in the circumferential direction of thearticulating member 69 until reaching the slot 692, passes inwardlythrough the slot 692, and extends on the inner circumference of thearticulating member 69 in the proximal direction to the control wheel Gin the control body 3.

The control wire 9 is thus divided into a first section 91 that extendsfrom the control wheel G in the control body 3 to the slot 691, a secondsection 92 that extends from the slot 691 on the outer circumference ofthe articulating member 69 in the circumferential direction of thearticulating member 69 to the slot 692, and a third section 93 thatextends from the slot 692 to the control wheel G in the control body 3.

The control wire 9 is tensioned, and the angled section A is thus bent,by rotating the control wheel G in the tensioning direction, due to thefact that the third section 93 that is anchored on the articulatingmember 69 is pushed in the proximal direction. The third section 93 ofthe control wire 9 thus forms a distal anchoring section of the controlwire 9.

Manufacturing Method

The insertion tube 2 according to the invention is manufactured from asingle tube element that is cut by laser. The tube element is made of arelatively hard material such as stainless steel, or also a suitablehard plastic. Due to the cuts, the initially hard tube element becomesflexible, but maintains its rigidity.

The cuts create the respective lateral indentations S in the proximalpassive flexible section 20, the hole 77, the cut 70 in the transitionarea K, the hole 631, the respective articulating members 6 in thedistal angled section A, and the slots 691, 692. This sequence is not tobe construed as limiting. For example, the slots 691, 692 may be cutbefore the articulating members 6. In addition, the order of the cutsmay also be reversed.

The flexibility and also the rigidity of the tube element may becontrolled based on the shape, arrangement, and size of the cuts.

The location of the particular cuts may be calculated in advance andpredetermined. The predefined data for the particular cuts may be inputinto a programmable laser cutting machine in order to automaticallyproduce the insertion tube 2.

The individual articulating members 6 are completely cut out, and formseparate bodies that are connected only in a form-fit manner.

After the laser cutting of the tube element, the brackets 72 and thecable guide lugs 630 are bent inwardly. The blank for the insertion tube2 is finished in this way.

The control wire 9 may now be inserted and fastened in this blank forthe insertion tube 2. The blank for the insertion tube 2 may be fastenedto the control body 3. In addition, a covering, preferably made ofmetal, that encloses the blank for the insertion tube 2 and shields theelectrical control system may be applied to the blank for the insertiontube 2, and an elastic sheath made of plastic or rubber may be fitted onsame. The plastic or rubber elastic sheath may be subjected to thermalshrinkage.

Second Exemplary Embodiment

A second exemplary embodiment of the present invention is describedbelow with reference to FIGS. 17 through 19.

In the first exemplary embodiment, the individual articulated joints areformed in the bending section based on cuts in such a way that the cutshave protrusions and depressions in the direction of extension of theendoscope. The protrusions rest in the depressions of the adjacentarticulated joint to allow a swivel movement of the articulated joint.In other words, in the first exemplary embodiment the individualarticulated joints are connected in a form-fit manner.

FIGS. 17 through 19 show the angled section A′ as a bending section ofthe second exemplary embodiment. In the second exemplary embodiment,only straight cuts 801, 802, 811, 812 are provided in the bendingsection A′.

The bending section A′ is provided with a plurality of cuts 801, 802oriented perpendicularly with respect to the axis of the bending sectionA′. More precisely, the cuts 801, 802 are designed in such a way that acut 801 is made from above, through the tube element perpendicular tothe axis of the tube element, to a depth that ends prior to the centeraxis area. In addition, a cut 802 is made from below, through the tubeelement perpendicular to the axis of the tube element, to a depth thatlikewise ends prior to the center axis area. The cuts 801 and 802 aresituated on a plane, and their ends are situated opposite from oneanother with a space 803 left in between. The space 803 is an uncutspace in the center axis area of the tube element. The cuts 801 areparallel to one another. The cuts 802 are analogously likewise parallelto one another.

The straight cuts 801, 802 function as an articulated joint and allowthe bending movement of the bending section A′.

A predefined number of successive cuts 801 (and analogously 802, ofcourse) in the longitudinal direction of the bending section A′ arecombined to form a group. In FIG. 18, every 10 cuts 801 belong to agroup, wherein the number of cuts 801, 802 for each group may beappropriately selected as desired. The more cuts 801, 802 a group has,the larger the bending angle in the area of this group.

Each group of cuts 801, 802 is delimited in the longitudinal directionof the bending section A′ by an annular section 805 having short cuts811, 812.

More precisely, the short cuts 811, 812 are designed in such a way thata short cut 811 is made from above, through the tube elementperpendicularly in the direction of the axis of the tube element, to avery small depth, as shown in FIG. 17. This small depth may be, forexample, one-tenth to one-twentieth the diameter of the tube element.This results in a short length of the particular cut 811, 812, as shownin FIG. 18, in which short cuts 811 are shown from above. The length ofthe short cuts 811, 812 may be appropriately selected as desired.

In addition, a respective short cut 812 from below is made, similarly asfor the short cuts 811 from above. The cuts 811 are parallel to oneanother. The cuts 812 are analogously likewise parallel to one another.

The short cuts 811 and 812 each form a pair, and in each case aresituated on a plane, and their ends are situated opposite from oneanother with a space left in between which forms the annular section805. The annular section 805 is a section of the tube elements havingonly one pair of short cuts 811, 812.

The material of the tube element situated adjacent to the particularshort cuts 811, 812 forms a strip section. This strip section forms acable guide lug 880 when it is bent toward the center of the tubeelement, as shown in FIG. 19. A traction cable may thus be guided in thespace that is formed between the outwardly pointing face of the stripsection of the cable guide lug 880 and the inner circumferential surfaceof the tube element that is adjacent in the longitudinal direction.

The straight cuts 801, 802 may be provided on the bending section A′ insuch a way that the rigidity is similar to that in the first exemplaryembodiment.

The machine run time necessary for manufacturing the articulated jointsand cable guide lugs may be reduced significantly by providing thestraight cuts 801, 802, 811, 812, thus lowering the production costs.

Further Alternatives

In the exemplary embodiment, viewed in the proximal direction theflexible section 20 has a first zone B, a second zone C, and a thirdzone D having different degrees of flexibility. The number of zones orareas with different flexibilities is not limited. The flexible section20 may also have more or fewer zones with different flexibilities. Theinvention is also applicable to an insertion tube in which the flexiblesection 20 has a uniform flexibility throughout.

In the exemplary embodiment, the tube element of the insertion tube 2 ismade of stainless steel. The invention is not limited thereto. Thematerial of the insertion tube 2 may be any given material havingsufficient rigidity, such as a hard plastic. In another alternative,Nitinol (a nickel-titanium alloy) may be used as the tube material. Thismaterial has the property, among others, of so-called superelasticity;i.e., it may be elastically deformed over a wide range without beingpermanently distorted.

In one alternative, cuts are provided in the tube element by a lasercutting machine. These cuts may be provided very precisely. Therefore,manufacture by laser is preferred. In principle, however, it isconceivable to also make these cuts by other manufacturing methods suchas sawing, wire sawing, etc.

In the exemplary embodiment, the angled section A may be bent in twoangular directions, namely, upwardly and downwardly in FIGS. 6 and 7. Inone alternative, the individual articulating members 6 may be designedin such a way that their heads 622, from articulating member 6 toarticulating member 6, are rotated with an offset of 90 degrees aboutthe axis of the angled section A (axis of the articulating members 6).In this alternative, the angled section A may be bent in four angulardirections, namely, upwardly and downwardly, and toward and away fromthe observer, in FIGS. 6 and 7, respectively.

In the alternative in which the angled section A may be bent in fourangular directions, two control wires 9 may be used that extend in theinsertion tube 2 with an offset of 90 degrees relative to one another.The articulating member 92 is then provided with four distal slots,which likewise are offset by 90 degrees relative to one another.

In the exemplary embodiment, a particular articulating member 6 has adesign with the described shape. The invention is not limited withregard to the shape of the articulating member 6. It is sufficient forarticulating members that are coupled to one another, and that allow adeflection movement of the angled section A, to be cut in the angledsection A.

The invention may be advantageously used in a duodenoscope, agastroscope, a colonoscope, or a similar endoscope. The principle of theinvention may also be applied to any other given type of endoscope.

The principle of the invention may also be applied to other medicaldevices that use an insertion tube.

REFERENCE SIGNS LIST

-   -   1 endoscope    -   2 insertion tube    -   3 control body    -   6 articulating member    -   8 guide spring    -   9 control wire    -   20 flexible section    -   61 articulating member    -   62 articulating member    -   63 articulating member    -   69 articulating member situated farthest on the distal side    -   70 section    -   71 hinge    -   72 bracket    -   73 lower lug    -   74 upper lug 74    -   75 bracket middle piece    -   77 hole    -   91 first section of the control wire    -   92 second section of the control wire    -   93 third section of the control wire    -   201 cut from above    -   202 cut from below    -   203 uncut space    -   204 cut from the side    -   601 head line    -   602 neck line    -   603 shoulder line    -   604 arm line    -   605 arm end line    -   606 bent foot line    -   607 base line    -   608 straight foot line    -   609 stomach line    -   621 main body    -   622 head    -   623 arm    -   624 foot    -   630 cable guide lug    -   631 central hole    -   691 slot    -   692 slot    -   801 cut from above    -   802 cut from below    -   803 uncut space    -   805 annular section with short cuts    -   811 short cut from above    -   812 short cut from below    -   880 cable guide lug    -   A angled section    -   A′ angled section    -   B first zone (distal area)    -   C second zone (middle area)    -   D third zone (proximal area)    -   F first control wheel (first control element)    -   G second control wheel (second control element)    -   J control body housing    -   K transition area    -   S lateral indentation on the flexible section

1. A method for manufacturing an endoscope insertion tube (2), whereinthe insertion tube (2) has a proximal passive flexible section (20) anda distal angled section (A), characterized in that the entire insertiontube, including the passive flexible section (20) and the angled section(A), is formed from a single tube element.
 2. The method according toclaim 1, wherein the entire insertion tube (2), including the passiveflexible section (20) and the angled section (A), is cut from a singletube element by laser.
 3. The method according to claim 1, whereinindividual cuts are made in the tube element.
 4. The method according toclaim 1, wherein the distal angled section (A) has inwardly bent guideprotrusions (630) on which a traction cable (9) is supported; whereinthe inwardly bent guide protrusions (630) are cut from thecircumferential wall of the distal angled section (A) and then bentinwardly.
 5. The method according to claim 1, wherein at the transition(K) from the proximal passive flexible section (20) and the distalangled section (A), the insertion tube (2) has an inwardly bent bracket(72) on which a guide spring (8) is supported; wherein the inwardly bentbracket (72) is cut from the circumferential wall of the insertion tube(2) and then bent inwardly.
 6. The method according to claim 1, whereinmultiple articulated joints (6) are produced in the circumferential wallof the distal angled section (A) by cutting.
 7. The method according toclaim 6, wherein the particular articulated joint (6) produced bycutting has a coupling section (622) that is coupled to an adjacentarticulated joint (6), produced by cutting, in such a way that an axialmovement, but not a radial movement, of the articulated joints (6)relative to one another is blocked, and a guide section (624) thatengages with an adjacent articulated joint (6), produced by cutting, insuch a way that an axial movement of the articulated joints (6) relativeto one another is made possible.
 8. The method according to claim 1,wherein the proximal passive flexible section (20) is produced byrespective lateral indentations (S) that are provided perpendicular tothe longitudinal extension of the tube element.
 9. The method accordingto claim 8, wherein in the longitudinal extension of the tube element,the proximal passive flexible section (20) has at least two subsections(B, C, D) which include the respective lateral indentations (S) atdifferent spacings from one another in the longitudinal extension of thetube element.
 10. The method according to claim 1, wherein the tubeelement is made of stainless steel or plastic.
 11. (canceled)
 12. Themethod according to claim 1, wherein from a control body (3) situatedproximally from the proximal passive flexible section (20), a tractioncable (9) is situated on the inner circumferential side of the tubeelement, and at an articulated joint (69) of the distal angled section(A) situated farthest distally, the traction cable is led through afirst slot (691) in a wall of the tube element to the outercircumference of the tube element, around the outer circumference of thetube element, to a second slot (692) in the wall of the tube element tothe inner circumference of the tube element, wherein the second slot(692) is opposite the first slot (691) by 180 degrees, and is led backto the control body (3) on the inner circumferential side of the tubeelement.
 13. An endoscope having an insertion tube, wherein theinsertion tube (2) has a proximal passive flexible section (20) and adistal angled section (A), characterized in that the entire insertiontube (2), including the proximal passive flexible section (20) and thedistal angled section (A), is formed from a single tube element.
 14. Theendoscope according to claim 13, wherein the distal angled section (A)has inwardly bent guide protrusions (630) on which a traction cable (9)is supported.
 15. The endoscope according to claim 13, wherein at thetransition from the proximal passive flexible section (20) and thedistal angled section (A), the insertion tube (2) has an inwardly bentbracket (72) on which a guide spring (8) is supported.
 16. The endoscopeaccording to claim 13, wherein multiple articulated joints (6) areformed in the circumferential wall of the distal angled section (A). 17.The endoscope according to claim 16, wherein the particular articulatedjoint (6) has a coupling section (622) that is coupled to an adjacentarticulated joint (6) in such a way that an axial movement, but not aradial movement, of the articulated joints (6) relative to one anotheris blocked, and a guide section (624) that engages with an adjacentarticulated joint (6) in such a way that an axial movement of thearticulated joints (6) relative to one another is made possible.
 18. Theendoscope according to claim 13, wherein the tube element is made ofstainless steel.
 19. The endoscope according to claim 13, wherein thetube element is made of plastic.
 20. The endoscope according to claim13, wherein the tube element is made of a nickel-titanium alloy.
 21. Theendoscope according to claim 13, wherein from a control body (3)situated proximally from the proximal passive flexible section (20), atraction cable (9) is situated on the inner circumferential side of thetube element, and at an articulated joint (69) of the distal angledsection (A) situated farthest distally, the traction cable is ledthrough a first slot (691) in a wall of the tube element to the outercircumference of the tube element, around the outer circumference of thetube element, to a second slot (692) in the wall of the tube element tothe inner circumference of the tube element, wherein the second slot(692) is opposite the first slot (691) by 180 degrees, and is led backto the control body (3) on the inner circumferential side of the tubeelement.